Filled polymeric composites including short length fibers

ABSTRACT

Polymeric composites and methods for preparing the composites are described herein. The polymeric composites can comprise a polymer, an inorganic filler, and a plurality of short length fibers. The polymer in the composites can include homopolymers and copolymers and can also include plastics, resins, elastomers, thermoplastics, thermosets, and hot melts. The inorganic filler can be fly ash. The short length fibers can have an average length of 650 μm or less. Methods for making the polymeric composites are also described.

FIELD OF THE DISCLOSURE

This disclosure relates generally to filled polymers, more particularly,to the use of short length fibers in polymeric composites.

BACKGROUND OF THE DISCLOSURE

Organic-inorganic composite materials have become desirable for avariety of uses because of their excellent mechanical properties andweathering stability. In general, the superior properties oforganic-inorganic composites are achieved through the use of the organicas a matrix material that acts as a glue with enhanced flexuralproperties or as a fibrous component providing reinforcement, improvedtensile properties, and resistance to degradation from weathering of thecomposite when it is exposed to the environment. The inorganic materialimparts various properties of rigidity, toughness, hardness, opticalappearance and interaction with electromagnetic radiation, density, andmany other physical and chemical attributes. Thus, organic-inorganiccomposite materials can be used in a variety of applications.Nevertheless, there is a continuing desire to improve the properties offilled composites.

SUMMARY OF THE DISCLOSURE

Polymeric composites and methods for preparing the composites aredescribed herein. The polymeric composites can comprise a polymer, aninorganic filler, and a plurality of short length fibers. The polymer inthe composites can include homopolymers and copolymers and can alsoinclude plastics, resins, elastomers, thermoplastics, thermosets, andhot melts.

The inorganic filler can be in an amount from 25% to 90% by weight ofthe polymeric composite. For example, the inorganic filler can bepresent in an amount from 50% to 80% by weight, based on the totalweight of the composite. In some embodiments, the inorganic fillercomprises fly ash.

The short length fibers can be any natural or synthetic fiber material,based on inorganic materials, organic materials, or combinations ofboth. Suitable short length fibers for use in the polymeric compositesinclude mineral wool, cellulose, wood fiber, saw dust, wood shavings,cotton, lint, and combinations thereof. In some embodiments, the shortlength fiber is mineral wool. In some embodiments, the short lengthfibers are coated with an aminosilane. The short length fibers can bepresent in an amount of from 0.5% to 15% by weight, based on the totalweight of the composite. The short length fibers can have an averagelength of 650 μm or less. For example, the short length fibers can havean average length of from 50 μm to 650 μm or from 100 μm to 250 μm. Theshort length fibers can have an average diameter of from 1 to 20 μm. Theshort length fibers can also be described by their average aspectratio—the ratio of the length to the diameter. In some embodiments, theshort length fibers in the polymeric composites can have an averageaspect ratio of from 5:1 to 250:1 or from 8:1 to 250:1.

Suitable polymers for use in the polymeric composites includepolyolefins, ethylene copolymers, polystyrenes, polyvinyl chlorides,polyvinylidene chlorides, polyvinyl acetates, polyacrylonitriles,polyamides, polyisobutylenes, polyacetals, chlorinated and fluorinatedpolymers, fluoroelastomers, fluorosilicones, polycarbonates, epoxies,phenolics, polyesters, acrylic polymers, acrylate polymers,polyurethanes, alkyds, silicones, styrene-butadiene copolymers,acrylonitrile-butadiene-styrene copolymers, nitrile rubbers, diallylphthalates, melamines, polybutadienes, aramids, cellulosics, celluloseacetobutyrates, ionomers, parylenes, polyaryl ethers, polyaryl sulfones,polyarylene sulfides, polyethersulfones, polyallomers, polyimides,polyamideimides, polymethylpentenes, polyphenylene oxides, polyphenylenesulfides, polysulfones, polyetherketones, polyetherimides,polyaryleneketones, polychloroprenes, and blends thereof. The polymercan be present in an amount of from 10% to 60% by weight, based on thetotal weight of the composite.

In some embodiments, the polymer can be a polyurethane. The polyurethanecan be formed by the reaction of at least one isocyanate selected fromthe group consisting of diisocyanates, polyisocyanates and mixturesthereof, and at least one polyol. The at least one polyol can comprisean aromatic polyester polyol. In some embodiments, the reaction can bein the presence of a catalyst.

The polymeric composites can further include a plurality of glass fibershaving a minimum length of 1 mm (e.g., a minimum length of 3 mm). Theglass fiber can be present in an amount from 0.5% to 10% by weight,based on the total weight of the composite.

Methods for making the polymeric composites are also described. Themethod can include mixing the inorganic filler, the short length fibers,and the polymer, to form a composite mixture. The composite mixture canhave a viscosity of from 25 Pa·s to 250 Pa·s (e.g., from 80 Pa·s to 250Pa·s). In some specific embodiments, where the polymer is apolyurethane, the method can include mixing an inorganic filler, atleast one isocyanate selected from the group consisting ofdiisocyanates, polyisocyanates, and combinations thereof, at least onepolyol, and the plurality of short length fibers to form the compositemixture. The method can further include allowing the at least oneisocyanate and the at least one polyol to react in the presence of theinorganic filler, and the plurality of short length fibers to form thepolymeric composite. In some embodiments, the composite mixture canfurther include a catalyst. In some embodiments, the composite mixturecan also include a plurality of glass fibers having a minimum length of1 mm (e.g., a minimum length of 3 mm).

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a graph showing the flexural strength of polyurethanecomposites with and without mineral wool, as a function of thecomposite's bulk density.

FIG. 2 is a graph showing the flexural strength of polyurethanecomposites with mineral wool, as a function of the composite's bulkdensity.

FIG. 3 is a graph showing the flexural strength of polyurethanecomposites with 7% mineral wool or 2% sand, as a function of thecomposite's bulk density.

DETAILED DESCRIPTION

Polymeric composites and methods for preparing the composites aredescribed herein. The polymeric composites can comprise a polymer, aninorganic filler, and a plurality of short length fibers.

The polymer in the composites can include homopolymers and copolymersand can include plastics, resins, elastomers, thermoplastics,thermosets, and hot melts. Polymers suitable for use in the polymericcomposite include polyolefins (e.g., polyethylene or polypropylene),ethylene copolymers (e.g., ethylene-acrylic copolymers andethylene-vinyl acetate copolymers), polystyrenes, polyvinyl chlorides,polyvinylidene chlorides, polyvinyl acetates, polyacrylonitriles,polyamides (e.g., nylon), polyisobutylenes, polyacetals, chlorinated andfluorinated polymers (e.g., PTFE), fluoroelastomers, fluorosilicones,polycarbonates, epoxies, phenolics, polyesters, acrylic polymers,acrylate polymers, polyurethanes, alkyds, silicones, styrene-butadiene(SB) copolymers, acrylonitrilebutadiene-styrene (ABS) copolymers,nitrile rubbers, diallyl phthalates, melamines, polybutadienes, aramids,cellulosics, cellulose acetobutyrates, ionomers, parylenes, polyarylethers, polyaryl sulfones, polyarylene sulfides, polyethersulfones,polyallomers, polyimides, polyamideimides, polymethylpentenes,polyphenylene oxides, polyphenylene sulfides, polysulfones,polyetherketones, polyetherimides, polyaryleneketones, polychloroprenes,and blends thereof. In some embodiments, the polymer includespolyethylene, polypropylene, polyvinyl chloride, nylon, epoxy, phenolic,polyester, acrylic polymer, acrylate polymer, polyurethane, styrenebutadiene copolymer, acrylonitrile-butadiene-styrene copolymer, or ablend thereof.

In some embodiments, the polymer in the polymeric composite can be apolyurethane. The polyurethane composites can be formed using highlyreactive systems such as highly reactive polyols, isocyanates, or both.For example, the composites can be formed by the reaction of at leastone isocyanate, selected from the group consisting of diisocyanates,polyisocyanates, and mixtures thereof, and at least one polyol, in thepresence of an inorganic filler. In some embodiments, the reaction canbe in the presence of a catalyst.

Isocyanates suitable for use in the polyurethane composite describedherein include one or more monomeric or oligomeric poly- ordi-isocyanates. The monomeric or oligomeric poly- or di-isocyanateinclude aromatic diisocyanates and polyisocyanates. The isocyanates canalso be blocked isocyanates, or pre-polymer isocyanates (e.g., castoroil pre-polymer isocyanates and soy polyol pre-polymer isocyanates). Anexample of a useful diisocyanate is methylene diphenyl diisocyanate(MDI). Useful MDI's include MDI monomers, MDI oligomers, and mixturesthereof.

Further examples of useful isocyanates include those having NCO (i.e.,the reactive group of an isocyanate) contents ranging from about 25% toabout 35% by weight. Examples of useful isocyanates are found, forexample, in Polyurethane Handbook: Chemistry, Raw Materials, ProcessingApplication, Properties, 2^(nd) Edition, Ed: Gunter Oertel;Hanser/Gardner Publications, Inc., Cincinnati, Ohio, which is hereinincorporated by reference. Suitable examples of aromatic polyisocyanatesinclude 2,4- or 2,6-toluene diisocyanate, including mixtures thereof;p-phenylene diisocyanate; tetramethylene and hexamethylenediisocyanates; 4,4-dicyclohexylmethane diisocyanate; isophoronediisocyanate; 4,4-phenylmethane diisocyanate; polymethylenepolyphenylisocyanate; and mixtures thereof. In addition, triisocyanatesmay be used, for example, 4,4,4-triphenylmethane triisocyanate;1,2,4-benzene triisocyanate; polymethylene polyphenyl polyisocyanate;methylene polyphenyl polyisocyanate; and mixtures thereof. Suitableblocked isocyanates are formed by the treatment of the isocyanatesdescribed herein with a blocking agent (e.g., diethyl malonate,3,5-dimethylpyrazole, methylethylketoxime, and caprolactam). Isocyanatesare commercially available, for example, from Bayer Corporation(Pittsburgh, Pa.) under the trademarks MONDUR and DESMODUR. Otherexamples of suitable isocyanates include MONDUR MR Light (BayerCorporation; Pittsburgh, Pa.), PAPI 27 (Dow Chemical Company; Midland,Mich.), Lupranate M20 (BASF Corporation; Florham Park, N.J.), LupranateM70L (BASF Corporation; Florham Park, N.J.), Rubinate M (HuntsmanPolyurethanes; Geismar, La.), Econate 31 (Ecopur Industries), andderivatives thereof.

The average functionality of isocyanates useful with the compositesdescribed herein is between about 1.5 to about 5. Further, examples ofuseful isocyanates include isocyanates with an average functionality ofabout 2 to about 4.5, about 2.2 to about 4, about 2.4 to about 3.7,about 2.6 to about 3.4, and about 2.8 to about 3.2.

The at least one polyol for use in the polyurethane composite caninclude polyester polyols, polyether polyols, or combinations thereof.In some embodiments, the at least one polyol can include 50% or more ofone or more highly reactive (i.e., first) polyols. For example, the atleast one polyol can include greater than 55%, greater than 60%, greaterthan 65%, greater than 70%, greater than 75%, greater than 80%, greaterthan 85%, greater than 90%, greater than 95%, or 100% of one or morehighly reactive polyols.

In some embodiments, the one or more highly reactive polyols can includepolyols having a hydroxyl number of greater than 250. For example, thehydroxyl number can be greater than 275, greater than 300, greater than325, greater than 350, greater than 375, greater than 400, greater than425, greater than 450, greater than 475, greater than 500, greater than525, greater than 550, greater than 575, greater than 600, greater than625, greater than 650, greater than 675, greater than 700, greater than725, or greater than 750.

In some embodiments, the one or more highly reactive polyols can includepolyols having a primary hydroxyl number of greater than 250. As usedherein, the primary hydroxyl number is defined as the hydroxyl numbermultiplied by the percentage of primary hydroxyl groups based on thetotal number of hydroxyl groups in the polyol. For example, the primaryhydroxyl number can be greater than 255, greater than 260, greater than265, greater than 270, greater than 275, greater than 280, greater than285, greater than 290, or greater than 295.

In some embodiments, the one or more highly reactive polyols include alarge number of primary hydroxyl groups (e.g., 75% or more) based on thetotal number of hydroxyl groups in the polyol. For example, the highlyreactive polyols can include 80% or more, 85% or more, 90% or more, 95%or more, or 100% of primary hydroxyl groups. The number of primaryhydroxyl groups can be determined using fluorine NMR spectroscopy asdescribed in ASTM D4273, which is hereby incorporated by reference inits entirety.

In some embodiments, the one or more highly reactive polyols can includea Mannich polyol. Mannich polyols are the condensation product of asubstituted or unsubstituted phenol, an alkanolamine, and formaldehyde.Mannich polyols can be prepared using methods known in the art. Forexample, Mannich polyols can be prepared by premixing the phenoliccompound with a desired amount of the alkanolamine, and then slowlyadding formaldehyde to the mixture at a temperature below thetemperature of Novolak formation. At the end of the reaction, water isstripped from the reaction mixture to provide a Mannich base. See, forexample, U.S. Pat. No. 4,883,826, which is incorporated herein byreference in its entirety. The Mannich base can then be alkoxylated toprovide a Mannich polyol.

The substituted or unsubstituted phenol can include one or more phenolichydroxyl group. In certain embodiments, the substituted or unsubstitutedphenol includes a single hydroxyl group bound to a carbon in an aromaticring. The phenol can be substituted with substituents which do notundesirably react under the conditions of the Mannich condensationreaction, a subsequent alkoxylation reaction (if performed), or thepreparation of polyurethanes from the final product. Examples ofsuitable substituents include alkyl (e.g., a C₁-C₁₈ alkyl, or a C₁-C₁₂alkyl), aryl, alkoxy, phenoxy, halogen, and nitro groups.

Examples of suitable substituted or unsubstituted phenols that can beused to form Mannich polyols include phenol, o-, p-, or m-cresols,ethylphenol, nonylphenol, dodecylphenol, p-phenylphenol, variousbisphenols including 2,2-bis(4-hydroxyphenyl)propane (bisphenol A),β-naphthol, β-hydroxyanthracene, p-chlorophenol, o-bromophenol,2,6-dichlorophenol, p-nitrophenol, 4- or 2-nitro-6-phenylphenol,2-nitro-6- or 4-methylphenol, 3,5-dimethylphenol, p-isopropylphenol,2-bromo-6-cyclohexylphenol, and combinations thereof. In someembodiments, the Mannich polyol is derived from a phenol or a monoalkylphenol (e.g., a para-alkyl phenol). In some embodiments, the Mannichpolyol is derived from a substituted or unsubstituted phenol selectedfrom the group consisting of phenol, para-n-nonylphenol, andcombinations thereof.

The alkanolamine used to produce the Mannich polyol can include amonoalkanolamine, a dialkanolamine, or combinations thereof. Examples ofsuitable monoalkanolamines include methylethanolamine,ethylethanolamine, methylisopropanolamine, ethylisopropanolamine,methyl-2-hydroxybutylamine, phenylethanolamine, ethanolamine,isopropanolamine, and combinations thereof. Exemplary dialkanolaminesinclude diisopropanolamine, ethanolisopropanolamine,ethanol-2-hydroxybutylamine, isopropanol-2-hydroxybutylamine,isopropanol-2-hydroxyhexylamine, ethanol-2-hydroxyhexylamine, andcombinations thereof. In certain embodiments, the alkanolamine isselected from the group consisting of diethanolamine,diisopropanolamine, and combinations thereof.

Any suitable alkylene oxide or combination of alkylene oxides can beused to form the Mannich polyol. In some embodiments, the alkylene oxideis selected from the group consisting of ethylene oxide, propyleneoxide, butylene oxide, and combinations thereof. In certain embodiments,the Mannich polyol is alkoxylated with from 100% to about 80% propyleneoxide and from 0 to about 20 wt. % ethylene oxide.

Mannich polyols are known in the art, and include, for example, ethyleneand propylene oxide-capped Mannich polyols sold under the trade namesCARPOL® MX-425 and CARPOL® MX-470 (Carpenter Co., Richmond, Va.).

In some embodiments, the one or more first polyols can include anaromatic polyester, an aromatic polyether polyol, or a combinationthereof. In some embodiments, the one or more first polyols include anaromatic polyester polyol such as those sold under the TEROL® trademark(e.g., TEROL® 198).

Examples of highly reactive polyols also include Pel-Soy 744 and Pel-SoyP-750, soybean oil based polyols commercially available from PelronCorporation; Agrol Diamond, a soybean oil based polyol commerciallyavailable from BioBased Technologies; Ecopol 122, Ecopol 131 and Ecopol132, soybean oil polyols formed using polyethylene terephthalate andcommercially available from Ecopur Industries; Stepanpol PD-110 LV andPS 2352, polyols based on soybean oil, diethylene glycol and phthallicanhydride and commercially available from Stepan Company; Voranol 280,360 and WR2000, polyether polyols commercially available from DowChemical Company; Honey Bee HB-530, a soybean oil-based polyolcommercially available from MCPU Polymer Engineering; Renewpol,commercially available from Styrotech Industries (Brooklyn Park, Minn.);JeffAdd B 650, a 65% bio-based content (using ASTM D6866-06) additivebased on soybean oil commercially available from Huntsman Polyurethanes;Jeffol SG 360, a sucrose and glycerin-based polyol commerciallyavailable from Huntsman Polyurethanes; and derivatives thereof. Forexample, Ecopol 131 is a highly reactive aromatic polyester polyolcomprising 80% primary hydroxyl groups, a hydroxyl number of 360-380 mgKOH/g, i.e., and a primary hydroxyl number of 288-304 mg KOH/g.

The at least one polyol for use in the polyurethane composites caninclude one or more plant-based polyols or non plant-based polyols. Insome embodiments, the plant-based polyols are highly reactive polyols.The one or more plant-based polyols useful in the polyurethanecomposites can include polyols containing ester groups that are derivedfrom plant-based fats and oils. Accordingly, the one or more plant-basedpolyols can contain structural elements of fatty acids and fattyalcohols. Starting materials for the plant-based polyols of thepolyurethane component can include fats and/or oils of plant-basedorigin with preferably unsaturated fatty acid residues. The one or moreplant-based polyols useful with the polyurethane composites include, forexample, castor oil, coconut oil, corn oil, cottonseed oil, lesquerellaoil, linseed oil, olive oil, palm oil, palm kernel oil, peanut oil,sunflower oil, tall oil, and mixtures thereof.

In some embodiments, the one or more polyols include a less reactivepolyol. For example, the polyurethane composite can be produced from oneor more less reactive polyols in addition to one or more highly reactivepolyols. Less reactive polyols can have lower hydroxyl numbers, lowernumbers of primary hydroxyl groups and/or lower primary hydroxyl numbersthan the highly reactive polyols. In some embodiments, the less reactivepolyols can have hydroxyl numbers of less than 250, less than 225, lessthan 200, less than 175, less than 150, less than 125, less than 100,less than 80, less than 60, less than 40, or even less than 20. In someembodiments, the less reactive polyols have about 50% or less primaryhydroxyl groups, about 40% or less primary hydroxyl groups, about 30% orless primary hydroxyl groups, about 20% or less primary hydroxyl groups,or even about 10% or less primary hydroxyl groups. In some embodiments,the less reactive polyols can have primary hydroxyl numbers of less thanabout 220, less than about 200, less than about 180, less than about160, less than about 140, less than about 120, less than about 100, lessthan about 80, less than about 60, less than about 40, or even less thanabout 20. Suitable less reactive polyols include castor oil; StepanpolPS-2052A (commercially available from the Stepan Company); Agrol 2.0,3.6, 4.3, 5.6 and 7.0 (plant-based polyols commercially available fromBioBased Technologies); Ecopol 123 and Ecopol 124, which arecommercially available from Ecopur Industries; Honey Bee HB-150 andHB-230, soybean oil-based polyols commercially available from MCPUPolymer Engineering; Terol 1154, commercially available from Oxid(Houston, Tex.); Multranol 3900, Multranol 3901, Arcol 11-34, Arcol24-32, Arcol 31-28, Arcol E-351, Arcol LHT-42, and Arcol LHT-112,commercially available from Bayer; and Voranol 220-028, 220-094,220-110N, 222-056, 232-027, 232-034, and 232-035, commercially availablefrom Dow.

The at least one polyol can include 50% or less of one or more lessreactive polyols in addition to the one or more highly reactive polyols.For example, the at least one polyol can include less than 45%, lessthan 40%, less than 35%, less than 30%, less than 25%, less than 20%,less than 15%, less than 10%, or less than 5%, of one or more lessreactive polyols.

The at least one polyol for use in the disclosure can have an averagefunctionality of 1.5 to 8.0, 1.6 to 6.0, 1.8 to 4.0, 2.5 to 3.5, or 2.6to 3.1. The average hydroxyl number values (as measured in units of mgKOH/g) for the at least one polyol can be from about 100 to 600, 150 to550, 200 to 500, 250 to 440, 300 to 415, and 340 to 400.

The polyurethane composites can include more than one type of polyol.The one or more polyols can be combined in various percentages, e.g.,15-40% of a less reactive polyol and 60-85% of a highly reactive polyol.

The polyurethane systems used to form the composite materials describedherein can include one or more additional isocyanate-reactive monomersin addition to the at least one polyol. The one or more additionalisocyanate-reactive monomers can include, for example, amine andoptionally hydroxyl groups.

In some embodiments, the one or more additional isocyanate-reactivemonomers can include a polyamine. The first isocyanate-reactive monomercan comprise a polyamine Any suitable polyamine can be used. Suitablepolyamines can correspond to the polyols described herein (for example,a polyester polyol or a polyether polyol), with the exception that theterminal hydroxy groups are converted to amino groups, for example byamination or by reacting the hydroxy groups with a diisocyanate andsubsequently hydrolyzing the terminal isocyanate group to an aminogroup. By way of example, the polyamine can be polyether polyamine, suchas polyoxyalkylene diamine or polyoxyalkylene triamine. Polyetherpolyamines are known in the art, and can be prepared by methodsincluding those described in U.S. Pat. No. 3,236,895 to Lee and Winfrey.Exemplary polyoxyalkylene diamines are commercially available, forexample, from Huntsman Corporation under the trade names Jeffamine®D-230, Jeffamine® D-400 and Jeffamine® D-2000. Exemplary polyoxyalkylenetriamines are commercially available, for example, from HuntsmanCorporation under the trade names Jeffamine® T-403, Jeffamine® T-3000,and Jeffamine® T-5000.

In some embodiments, the additional isocyanate-reactive monomer caninclude an alkanolamine. The alkanolamine can be a dialkanolamine, atrialkanolamine, or a combination thereof. Suitable dialkanolaminesinclude dialkanolamines which include two hydroxy-substituted C₁-C₁₂alkyl groups (e.g., two hydroxy-substituted C₁-C₈ alkyl groups, or twohydroxy-substituted C₁-C₆ alkyl groups). The two hydroxy-substitutedalkyl groups can be branched or linear, and can be of identical ordifferent chemical composition. Examples of suitable dialkanolaminesinclude diethanolamine, diisopropanolamine, ethanolisopropanolamine,ethanol-2-hydroxybutylamine, isopropanol-2-hydroxybutylamine,isopropanol-2-hydroxyhexylamine, ethanol-2-hydroxyhexylamine, andcombinations thereof. Suitable trialkanolamines include trialkanolamineswhich include three hydroxy-substituted C₁-C₁₂ alkyl groups (e.g., threehydroxy-substituted C₁-C₈ alkyl groups, or three hydroxy-substitutedC₁-C₆ alkyl groups). The three hydroxy-substituted alkyl groups can bebranched or linear, and can be of identical or different chemicalcomposition. Examples of suitable trialkanolamines includetriisopropanolamine (TIPA), triethanolamine,N,N-bis(2-hydroxyethyl)-N-(2-hydroxypropyl)amine (DEIPA),N,N-bis(2-hydroxypropyl)-N-(hydroxyethyl)amine (EDIPA),tris(2-hydroxybutyl)amine, hydroxyethyl di(hydroxypropyl)amine,hydroxypropyl di(hydroxyethyl)amine, tri(hydroxypropyl)amine,hydroxyethyl di(hydroxy-n-butyl)amine, hydroxybutyldi(hydroxypropyl)amine, and combinations thereof.

In some embodiments, the additional isocyanate-reactive monomer cancomprise an adduct of an alkanolamine described above with an alkyleneoxide. The resulting amine-containing polyols can be referred to asalkylene oxide-capped alkanolamines Alkylene oxide-capped alkanolaminescan be formed by reacting a suitable alkanolamine with a desired numberof moles of an alkylene oxide. Any suitable alkylene oxide orcombination of alkylene oxides can be used to cap the alkanolamine. Insome embodiments, the alkylene oxide is selected from the groupconsisting of ethylene oxide, propylene oxide, butylene oxide, andcombinations thereof. Alkylene oxide-capped alkanolamines are known inthe art, and include, for example, propylene oxide-cappedtriethanolamine sold under the trade names CARPOL® TEAP-265 and CARPOL®TEAP-335 (Carpenter Co., Richmond, Va.).

In some embodiments, the additional isocyanate-reactive monomer caninclude an alkoxylated polyamine (i.e., alkylene oxide-cappedpolyamines) derived from a polyamine and an alkylene oxide. Alkoxylatedpolyamine can be formed by reacting a suitable polyamine with a desirednumber of moles of an alkylene oxide. Suitable polyamines includemonomeric, oligomeric, and polymeric polyamines. In some cases, thepolyamines has a molecular weight of less than 1000 g/mol (e.g., lessthan 800 g/mol, less than 750 g/mol, less than 500 g/mol, less than 250g/mol, or less than 200 less than 200 g/mol). Examples of suitablepolyamines that can be used to form alkoxylated polyamines includeethylenediamine, 1,3-diaminopropane, putrescine, cadaverine,hexamethylenediamine, 1,2-diaminopropane, o-phenylenediamine,m-phenylenediamine, p-phenylenediamine, spermidine, spermine,norspermidine, toluene diamine, 1,2-propane-diamine, diethylenetriamine,triethylenetetramine, tetraethylene-pentamine (TEPA),pentaethylenehexamine (PEHA), and combinations thereof.

Any suitable alkylene oxide or combination of alkylene oxides can beused to cap the polyamine. In some embodiments, the alkylene oxide isselected from the group consisting of ethylene oxide, propylene oxide,butylene oxide, and combinations thereof. Alkylene oxide-cappedpolyamines are known in the art, and include, for example, propyleneoxide-capped ethylene diamine sold under the trade name CARPOL® EDAP-770(Carpenter Co., Richmond, Va.) and ethylene and propylene oxide-cappedethylene diamine sold under the trade name CARPOL® EDAP-800 (CarpenterCo., Richmond, Va.).

The additional isocyanate-reactive monomer (when used) can be present invarying amounts relative the at least one polyol used to form thepolyurethane. In some embodiments, the additional isocyanate-reactivemonomer can be present in an amount of 30% or less, 25% or less, 20% orless, 15% or less, 10% or less, or 5% or less by weight based on theweight of the at least one polyol.

As indicated herein, in the polyurethane composites, an isocyanate isreacted with a polyol (and any additional isocyanate-reactive monomers)to produce the polyurethane formulation. In general, the ratio ofisocyanate groups to the total isocyanate reactive groups, such ashydroxyl groups, water and amine groups, is in the range of about 0.5:1to about 1.5:1, which when multiplied by 100 produces an isocyanateindex between 50 and 150. Additionally, the isocyanate index can be fromabout 80 to about 120, from about 90 to about 120, from about 100 toabout 115, or from about 105 to about 110. As used herein, an isocyanatemay be selected to provide a reduced isocyanate index, which can bereduced without compromising the chemical or mechanical properties ofthe composite material.

One or more catalysts can be added to facilitate curing and can be usedto control the curing time of the polyurethane matrix. Examples ofuseful catalysts include amine-containing catalysts (such as DABCO,tetramethylbutanediamine, and diethanolamine) and tin-, mercury-, andbismuth-containing catalysts. In some embodiments, 0.01 wt % to 2 wt %catalyst or catalyst system (e.g., 0.025 wt % to 1 wt %, 0.05 wt % to0.5 wt %, or 0.1 wt % to about 0.25 wt %) can be used.

The polymer can be present in the polymeric composite in amounts from10% to 60% based on the weight of polymeric composite. For example, thepolymer can be included in an amount of 15% to 55% or 20% to 50% byweight, based on the weight of the polymer composite. In someembodiments, the polymer in the polymeric composites can be present inan amount of 10% or greater, 15% or greater, 20% or greater, 25% orgreater, 30% or greater, 35% or greater, 40% or greater, 45% or greater,50% or greater, or 55% or greater by weight, based on the weight ofpolymeric composite. In some embodiments, the polymer in the polymericcomposites can be present in an amount of 60% or less, 55% or less, 50%or less, 45% or less, 40% or less, 35% or less, 30% or less, 25% orless, 20% or less, or 15% or less by weight, based on the weight ofpolymeric composite.

As described herein, the polymeric composites include a polymer, aninorganic filler, and a plurality of short length fibers. The inorganicfiller can be an ash, ground/recycled glass (e.g., window or bottleglass); milled glass; glass spheres; glass flakes; activated carbon;calcium carbonate; aluminum trihydrate (ATH); silica; sand; ground sand;silica fume; slate dust; crusher fines; red mud; amorphous carbon (e.g.,carbon black); clays (e.g., kaolin); mica; talc; wollastonite; alumina;feldspar; bentonite; quartz; garnet; saponite; beidellite; granite;calcium oxide; calcium hydroxide; antimony trioxide; barium sulfate;magnesium oxide; titanium dioxide; zinc carbonate; zinc oxide; nephelinesyenite; perlite; diatomite; pyrophillite; flue gas desulfurization(FGD) material; soda ash; trona; and mixtures thereof. The ash can be acoal ash or another type of ash such as those produced by firing fuelsincluding industrial gases, petroleum coke, petroleum products,municipal solid waste, paper sludge, wood, sawdust, refuse derivedfuels, switchgrass or other biomass material. The coal ash can be flyash, bottom ash, or combinations thereof. In some examples, theinorganic filler used is fly ash. Fly ash is produced from thecombustion of pulverized coal in electrical power generating plants. Thefly ash useful with the composite materials described herein can beClass C fly ash, Class F fly ash, or a mixture thereof. Fly ash producedby coal-fueled power plants is suitable for incorporation in thecomposites described herein.

In some embodiments, the inorganic filler present in the polymericcomposites can include sand. The sand can be present in the compositesin amounts from 0.1% to 5% by weight. In some embodiments, the inorganicfiller can include fly ash and sand.

The inorganic filler can be present in the polymeric compositesdescribed herein in amounts from 25% to 90% by weight. In someembodiments, the inorganic filler can be present in amounts from 40% to85%, 45% to 85%, 50% to 85%, 55% to 85%, 60% to 85%, or 60% to 80% byweight. Examples of the amount of inorganic filler present in thecomposites described herein include 25%, 30%, 31%, 32%, 33%, 34%, 35%,36%, 37%, 38%, 39%, 40%, 41%, 42%, 43%, 44%, 45%, 46%, 47%, 48%, 49%,50%, 51%, 52%, 53%, 54%, 55%, 56%, 57%, 58%, 59%, 60%, 61%, 62%, 63%,64%, 65%, 66%, 67%, 68%, 69%, 70%, 71%, 72%, 73%, 74%, 75%, 76%, 77%,78%, 79%, 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, or 90%.

In addition to an inorganic filler, the composite can include an organicfiller, such as a recycled polymeric material. Suitable examples includepulverized polymeric foam or recycled rubber material

The inclusion of fillers in the polyurethane composite as describedherein can modify and/or improve the chemical and mechanical propertiesof the composite. For example, the optimization of various properties ofthe composite allows their use in building materials and otherstructural applications.

The polymeric composites can also include a plurality of short lengthfibers. The short length fibers can be any natural or synthetic fibermaterial, based on inorganic materials, organic materials, orcombinations of both. Exemplary inorganic short length fibers that canbe used in the polymeric composite include mineral wool fibers such asstone wool, slag wool, or ceramic fiber wool. The mineral wool fiberscan be synthetic or can be obtained from molten mineral such as lava,rock or stone. Other suitable inorganic short length fibers includebasalt fibers, wollastonite fibers, alumina silica fibers, aluminumoxide fibers, silica fibers, carbon fibers, metal fibers, andcombinations thereof. Exemplary organic short length fibers that can beused in the polymeric composite include hemp fibers, sisal fibers,cotton fibers, straw, reeds, or other grasses, jute, bagasse fibers,abaca fibers, flax, southern pine fibers, wood fibers, cellulose, lint,vicose, leather fibers, and mixtures thereof. Other suitable organicshort length fibers include synthetic fibers such as, Kevlar, viscosefibers, polyamide fibers, polyacrylonitrile fibers, Dralon® fibers,polyethylene fibers, polypropylene fibers, polyvinylalcohol fibers,aramid fibers, carbon fibers, or combinations thereof. In someembodiments, the polymeric composites can include a combination offibers that break and fibers that do not break when the composite isfractured by external stress.

The short length fibers in the polymeric composites can be from 50 μm to650 μm in average (mean) length (i.e., can have an average length offrom 50 μm to 650 μm). For example, the short length fibers can have anaverage length of 50 μm or greater, 60 μm or greater, 70 μm or greater,80 μm or greater, 90 μm or greater, 100 μm or greater, 110 μm orgreater, 120 μm or greater, 130 μm or greater, 140 μm or greater, 150 μmor greater, 160 μm or greater, 170 μm or greater, 180 μm or greater, 190μm or greater, 200 μm or greater, 220 μm or greater, 240 μm or greater,260 μm or greater, 280 μm or greater, 300 μm or greater, 320 μm orgreater, or 350 μm or greater. In some embodiments, the short lengthfibers can have an average length of 650 μm or less, 600 μm or less, 550μm or less, 500 μm or less, 450 μm or less, 400 μm or less, 350 μm orless, 300 μm or less, 290 μm or less, 280 μm or less, 270 μm or less,260 μm or less, 250 μm or less, 240 μm or less, 230 μm or less, 220 μmor less, 210 μm or less, 200 μm or less, 190 μm or less, 180 μm or less,170 μm or less, 160 μm or less, 150 μm or less, 140 μm or less, 130 μmor less, 120 μm or less, 110 μm or less, 100 μm or less, 90 μm or less,80 μm or less, 70 μm or less, 60 μm or less, or 50 μm or less. In someexamples, the short length fibers in the polymeric composites can havean average length of from 50 μm to 650 μm, 75 μm to 650 μm, 100 μm to500 μm, 50 μm to 350 μm, or 100 μm or 250 μm. In some embodiments, thelengths of the short length fibers in the composite can be uniform (thelengths of all the fibers can be within 10% of the average length). Insome embodiments, the lengths of the short length fibers in thecomposite can vary. For example, the fiber lengths can fall into twomodes having an average length within the disclosed range. In someembodiments, all the short length fibers have a length of from 50 μm to650 μm, from 50 μm to 500 μm, from 50 μm to 350 μm, or from 100 μm or250 μm.

The short length fibers in the polymeric composites can have an averagediameter of from 1 μm to 20 μm. For example, the short length fibers canbe from 2 μm to 20 μm, 3 μm to 20 μm, 4 μm to 20 μm, 5 μm to 20 μm, 2 μmto 18 mμm, 3 μm to 18 μm, 4 μm to 18 μm, 5 μm to 18 μm, 2 μm to 15 μm, 3μm to 15 μm, 4 μm to 15 μm, or 5 μm to 15 μm in average diameter. Insome embodiments, the average diameter of the short length fibers can be3 μm, 3.5 μm, 4 μm, 4.5 μm, 5 μm, 5.5 μm, 6 μm, 6.5 μm, 7 μm, 7.5 μm, 8μm, 8.5 μm, 9 μm, 9.5 μm, or 10 μm. The diameter of the short lengthfibers in the composite can be uniform or varied.

The short length fibers can also be described by their aspect ratio. Insome embodiments, the short length fibers in the polymeric compositescan have an average aspect ratio of length to diameter of from 5:1 to250:1. For example, the short length fibers can have an average aspectratio of from 8:1 to 250:1, 10:1 to 250:1, 10:1 to 200:1, 10:1 to 150:1,10:1 to 100:1, 10:1 to 75:1, 10:1 to 50:1, 10:1 to 40:1, or 10:1 to30:1. In some embodiments, the short length fibers can have an averageaspect ratio of length to diameter of from 10:1 or greater, 15:1 orgreater, 20:1 or greater, 25:1 or greater, 30:1 or greater, or 40:1 orgreater. In some embodiments, the short length fibers can have anaverage aspect ratio of length to diameter of from 200:1 or less, 150:1or less, 100:1 or less, 75:1 or less, 50:1 or less, or 40:1 or less.

The short length fibers can be present in the polymeric composite in anysuitable amount to confer a desirable property to the polymericcomposite. The short length fibers can be present in the polymericcomposites in amounts from 0.5% to 15% by weight, based on the totalweight of the composite. For example, the short length fibers can be inamounts from 1% to 10%, 2% to 9%, or 3% to 8% by weight, based on thetotal weight of the composite. In some embodiments, the short lengthfibers can be present in the polymeric composites in amounts of 1% orgreater, 2% or greater, 3% or greater, 4% or greater, 5% or greater, 6%or greater, 7% or greater, 8% or greater, 9% or greater, or 10% orgreater, by weight, based on the total weight of the composite. In someembodiments, the short length fibers can be present in the polymericcomposites in amounts of 15% or less, 12% or less, 10% or less, 9% orless, 8% or less, 7% or less, 6% or less, or 5% or less by weight, basedon the total weight of the composite. In some embodiments, the shortlength fibers are present in the polymeric composites in an effectiveamount to increase the flexural strength and/or compressive strength ofthe composite, compared to a composite without the same.

In some embodiments, the fibers can be coated with a composition tomodify the reactivity of the fibers. For example, the fibers can becoated with a sizing agent such as a coupling agent (compatibilizer). Insome embodiments, the short length fibers can be coated with acomposition for promoting adhesion. U.S. Pat. No. 5,064,876 to Hamada etal. and U.S. Pat. No. 5,082,738 to Swofford, for example, disclosecompositions for promoting adhesion. In some embodiments, the shortlength fibers are surface coated with a composition comprising a silanecompound such as aminosilane. U.S. Pat. No. 4,062,999 to Kondo et al.and U.S. Pat. No. 6,602,379 to Li et al. describe suitable aminosilanecompounds for coating fibers. In some embodiments, the polymericcomposites can include a combination of coated and uncoated fibers.

Incorporation of the short length fibers in the polymeric composites canconfer advantageous properties such as increased flexural strength,increased compressive strength, low thermal conductivity, decreaseddensity, and/or decreased viscosity, compared to a polymeric compositewithout the same. The advantageous properties conferred by the shortlength fibers can be selected based on the concentration and/or thelength of the short length fibers in the composite. For example, theorientation of the short length fibers in the polymeric composites maybe characterized as being isotropic in nature, that is, the fiberorientation occurs in three dimensions rather than being limitedessentially to a planar dispersion. Said another way, referencing theorthogonal axes of a Cartesian coordinate system in which the x and yaxes define the laminar dimensions of the composite and the z axis thecross laminar dimension, the short length fibers can exhibit substantialorientation along both the x-y axes and the z-axis. Thus, for thinarticles, such as for example, an article about 6 mm thick, the shortlength fibers are capable of reinforcing the article along thez-direction as well as in the x-y plane.

The polymeric composites can further comprise glass fibers. “Glassfibers” as used herein, refers to fibrous glass derived from acombination of minerals, recycled materials, and virgin materials suchas sand, soda ash, and lime. Glass fibers can include fibrous glass suchas E-glass, C-glass, S-glass, and AR-glass fibers. The glass fibers canbe from 1 mm to 50 mm in average length. In some examples, the glassfibers are from 1 mm to 20 mm, from 2 mm to 20 mm, from 3 mm to 20 mm,or from 3 mm to 15 mm in average length. In some examples, the averagelength of the glass fibers in the polymeric composites can be 1 mm orgreater, 1.5 mm or greater, 2 mm or greater, 3 mm or greater, 4 mm orgreater, 5 mm or greater, or 6 mm or greater. In some embodiments, theaverage length of the glass fibers can be 50 mm or less, 40 mm or less,30 mm or less, 20 mm or less, 15 mm or less, 12 mm or less, or 10 mm orless. The glass fibers can be provided in a random orientation or can beaxially oriented. The glass fibers can be coated with a sizing agent tomodify their reactivity.

The glass fibers in the polymeric composites can have any dimension offrom 1 μm to 30 μm in average diameter. For example, the averagediameter of the glass fibers can be 2 μm to 25 μm, 3 μm to 20 μm, 4 μmto 18 μm, or 5 μm to 15 μm in average diameter. In some examples, theaverage diameter of the glass fibers in the polymeric composites can be1 mm or greater, 3 mm or greater, 5 mm or greater, 6 mm or greater, 7 mmor greater, 8 mm or greater, 9 mm or greater, or 10 mm or greater. Insome embodiments, the glass fibers in the polymeric composites can havea narrow distribution of diameters. For example, the glass can have adistribution wherein 95% or more of the fibers have a diameter that iswithin 10% of the average diameter.

The glass fibers (when used) can be present in the polymeric compositesin amounts from 0.5% to 10% by weight, based on the weight of polymericcomposite. For example, the glass fibers can be present in amounts from1% to 9%, 2% to 8%, 2.5% to 7.5%, or 3% to 7% by weight, based on theweight of the polymeric composite.

The glass fibers can provide increased strength, stiffness or toughnessto the polymeric composites. In some examples, fire resistant orretardant glass fibers can be included to impart fire resistance orretarding properties to the polymeric composites.

Additional components useful with the composite materials includefoaming agents, blowing agents, surfactants, chain-extenders,crosslinkers, coupling agents, UV stabilizers, fire retardants,antimicrobials, anti-oxidants, and pigments. Though the use of suchcomponents is well known to those of skill in the art, some of theseadditional additives are further described herein.

Chemical foaming agents include azodicarbonamides (e.g., Celogenmanufactured by Lion Copolymer Geismar); and other materials that reactat the reaction temperature to form gases such as carbon dioxide. Wateris an exemplary foaming agent. In some embodiments, water may be presentin the mixture in an amount of from greater than 0% to 5% by weight orless, based on the weight of the mixture. In some embodiments, water maybe present in the mixture in an amount of from 0.02%, 0.03%, 0.04%,0.05%, 0.10%, 0.15%, 0.2%, 0.25%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%,0.9%, 1%, 1.2%, 1.5%, or 1.6%, 1.7%, 1.8%, 1.9%, or 2%, by weight, basedon the weight of the mixture. For example, the water can be present in arange of 0.02% to 4%, 0.05% to 3%, 0.1% to 2%, or 0.2% to 1% by weight,based on the weight of the mixture. In some embodiments, the water ispresent from 0.04% to 2% or from 0.02% to 0.5% by weight, based on theweight of the mixture.

Surfactants can be used as wetting agents and to assist in mixing anddispersing the materials in the composite. Surfactants can be used, forexample, in amounts below about 0.5 wt % based on the total weight ofthe mixture. Examples of surfactants useful with the polymers describedherein include anionic, non-ionic and cationic surfactants. For example,silicone surfactants such as DC-197 and DC-193 (Air Products; Allentown,Pa.) can be used. Coupling agents and other surface treatments such asviscosity reducers, flow control agents, or dispersing agents can beadded directly to the filler or short length fibers, or incorporatedprior to, during, and/or after the mixing and reaction of the compositematerials. Coupling agents can allow higher filler loadings of aninorganic filler such as fly ash and may be used in small quantities.For example, the composite may comprise about 0.01 wt % to about 0.5 wt% of a coupling agent. Examples of coupling agents useful with thecomposite materials described herein include Ken-React LICA 38 andKEN-React KR 55 (Kenrich Petrochemicals; Bayonne, N.J.). Examples ofdispersing agents useful with the composite materials described hereininclude JEFFSPERSE X3202, JEFFSPERSE X3202RF, and JEFFSPERSE X3204(Huntsman Polyurethanes; Geismar, La.).

Ultraviolet light stabilizers, such as UV absorbers, can be added to thecomposite. Examples of UV light stabilizers include hindered amine typestabilizers and opaque pigments like carbon black powder. Fireretardants can be included to increase the flame or fire resistance ofthe composite material. Antimicrobials can be used to limit the growthof mildew and other organisms on the surface of the composite.Antioxidants, such as phenolic antioxidants, can also be added.Antioxidants provide increased UV protection, as well as thermaloxidation protection. Pigments or dyes can optionally be added to thecomposite materials described herein. An example of a pigment is ironoxide, which can be added in amounts ranging from about 2 wt % to about7 wt %, based on the total weight of the composite material.

The polymeric composite can be produced by mixing the polymer, theinorganic filler, and the plurality of short length fibers, in a mixingapparatus such as a high speed mixer or an extruder. In someembodiments, mixing can be conducted in an extruder. The materials canbe added in any suitable order. For example, in some embodiments, themixing stage of the method used to prepare the polymeric compositeincludes: (1) mixing the short length fibers with the inorganic fillerand the polymer, and (2) mixing the inorganic filler with the polymerand short length fibers. As discussed herein, in some embodiments, thepolymer is a polyurethane formed by a reaction of at least oneisocyanate and at least one polyol, optionally in the presence of acatalyst. Thus, in some embodiments, the mixing stage of the method usedto prepare the polyurethane composite includes: (1) mixing the polyol,short length fibers, and inorganic filler; (2) mixing the isocyanatewith the polyol, short length fibers, and the inorganic filler; andoptionally (3) mixing the catalyst with the isocyanate, the polyol, theshort length fibers, and the inorganic filler.

An ultrasonic device can be used for enhanced mixing and/or wetting ofthe various components of the composite. The ultrasonic device producesan ultrasound of a certain frequency that can be varied during themixing and/or extrusion process. The ultrasonic device useful in thepreparation of composite materials described herein can be attached toor adjacent to an extruder and/or mixer. For example, the ultrasonicdevice can be attached to a die or nozzle or to the port of an extruderor mixer. An ultrasonic device may provide de-aeration of undesired gasbubbles and better mixing for the other components, such as blowingagents, surfactants, and catalysts.

The mixture can then be extruded into a mold cavity of a mold, the moldcavity formed by at least an interior mold surface. The mold can be acontinuous forming system such as a belt molding system or can includeindividual batch molds. The belt molding system can include a moldcavity formed at least in part by opposing surfaces of two opposedbelts. A molded article can then be formed followed by removal of thearticle from the mold.

The polymer may be processed at an elevated temperature (e.g., 200-500F.) to form a melt and to allow the polymer to have a workableviscosity. In some embodiments, the inorganic filler is heated beforemixing with the polymer. The molten filled polymer (that is, thepolymer, the inorganic filler, and the short length fibers) can have aworkable viscosity of 25 Pa·s as to 250 Pa·s. Incorporation of the shortlength fibers into the filled polymer mixture can increase the viscosityof the mixture. In some embodiments, it is desirable that the compositemixture has a viscosity below a particular threshold at the desiredloadings so it can be effectively processed. In some embodiments, theshort length fibers can be present in the composite mixture in amountsto produce a workable viscosity of from 25 Pa·s to 250 Pa·s. Forexample, the short length fiber in the composite mixture can be inamounts to produce a workable viscosity from 50 Pa·s to 250 Pa·s, 65Pa·s to 250 Pa·s, or 80 Pa·s to 250 Pa·s. In some embodiments, theworking viscosity can be less than 250 Pa·s, less than 225 Pa·s, lessthan 200 Pa·s, less than 175 Pa·s, or less than 150 Pa·s. The viscosityof the composite mixture can be measured using a Thermo ElectronCorporation Haake Viscometer.

The polymeric composites preferably have a sufficiently high flexuralstrength. Incorporation of the short length fibers in the polymericcomposites can increase the flexural strength of the composite by atleast 8%, compared to a composite without short length fibers. In someembodiments, the flexural strength of the polymeric composites is atleast 10%, for example, 15% or greater, 20% or greater, 25% or greater,30% or greater, 35% or greater, 50% or greater, 75% or greater, or even100% or greater, compared to a composite without short length fibers.

The polymeric composites can be formed into shaped articles and used invarious applications including building materials. Examples of suchbuilding materials include siding material, roof coatings, roof tiles,roofing material, carpet backing, flexible or rigid foams such asautomotive foams (e.g., for dashboard, seats or roofing), componentcoating, and other shaped articles. Examples of shaped articles madeusing composite described herein include roofing material such as rooftile shingles; siding material; trim boards; carpet backing; syntheticlumber; building panels; scaffolding; cast molded products; deckingmaterials; fencing materials; marine lumber; doors; door parts;moldings; sills; stone; masonry; brick products; posts; signs; guardrails; retaining walls; park benches; tables; slats; and railroad ties.The composites described herein further can be used as reinforcement ofcomposite structural members including building materials such as doors;windows; furniture; and cabinets and for well and concrete repair. Thecomposites described herein also can be used to fill gaps, particularlyto increase the strength of solid surface articles and/or structuralcomponents. The composites can be flexible, semi-rigid or rigid foams.In some embodiments, the flexible foam is reversibly deformable (i.e.,resilient) and can include open cells. A 8″×1″×1″ piece of a flexiblefoam can generally wrap around a 1″ diameter mandrel at room temperaturewithout rupture or fracture. Flexible foams also generally have adensity of less than 5 lb/ft³ (e.g., 1 to 5 lb/ft³). In someembodiments, the rigid foam is irreversibly deformable and can be highlycrosslinked and/or can include closed cells. Rigid foams generally havea density of 5 lb/ft³ or greater (e.g., 5 to 60 lb/ft³, 20 to 55 lb/ft³,or 30 to 50 lb/ft³). In some embodiments, the overall density of themolded article can be 5 lb/ft³ or greater. For example, the overalldensity of the molded article can be 5 lb/ft³ to 80 lb/ft³, 10 lb/ft³ to70 lb/ft³, 15 lb/ft³ to 65 lb/ft³, 20 lb/ft³ to 60 lb/ft³, 25 lb/ft³ to55 lb/ft³, or 30 lb/ft³ to 50 lb/ft³.

EXPERIMENTAL

The following examples are put forth so as to provide those of ordinaryskill in the art with a complete disclosure and description of how thecomposites, articles, and/or methods claimed herein are made andevaluated, and are intended to be purely exemplary of the compositesdisclosed herein. Unless indicated otherwise, parts are parts by weight,temperature is in ° C. or is at ambient temperature, and pressure is ator near atmospheric.

Analysis of the Flow Properties, Densities, and Flexural Strengths ofPolyurethane Composites

Polyurethane composites were prepared using six different fibercompositions (Table 1, samples 1-6). The compositions were mixed with arotor operating at high rate of about 3000 rpm to impart high shear tothe mixture. The flow properties, densities, and flexural strengths ofthe polyurethane composites are shown in Table 1.

Analysis of the Flow Properties and Viscosities of PolyurethaneComposites

Polyurethane composites were prepared using nineteen different fibercompositions (Table 2, samples 7-25). Again, the compositions were mixedwith a rotor operating at high rate of about 3000 rpm. The flowproperties (under gravitation force) and viscosities of the polyurethanecomposites are shown in Table 2. The dimensions of the fibers are thesame as described in Table 1.

TABLE 1 Effect of fiber composition on the physical properties ofpolyurethane composites Sample ID 1 2 3 4 5 6 Polyurethane, wt % 27.027.0 27.0 27.0 27.0 27.0 Glass Fiber 3075, 3.175 mm length × 0.0 2.0 4.02.0 13 μm diameter, wt % Mineral Wool PLM, 150 μm length × 4.0 2.0 6 μmdiameter, wt % Mineral Wool RF825, 150 μm length × 4.0 5.5 μm diameter,aminosilane coated, wt % Class C Fly Ash, Scherer, wt % 73.0 71.0 69.069.0 69.0 69.0 Flow Property Flowable Semi-flowable Not flowableFlowable Flowable Semi-flowable Density, pcf 48.6 48.0 48.6 48.5 47.748.2 Flexural Strength, psi 1919 2270 2190 2070 2610 2260 % Increase inFlex Strength over N/A 18.3% 14.1% 7.8% 36.0% 17.8% Control Mix ID 1Normalized Flexural Strength, psi/pcf 39 47 45 43 54.7 47 % Increase innormalized Flex N/A 19.9% 14.5% 8.2% 38.6% 18.8% Strength over Mix ID 1

TABLE 2 Effect of fiber composition on the physical properties ofpolyurethane composites Glass Mineral Mineral Class C Fly Fiber Size,Poly Fiber Wool Wool Ash, Length (μm) × Mix MDI, 3075, PLM, RF825,Scherer, Diameter Viscosity¹ Flow ID wt % wt % wt % wt % wt % (μm) Pa ·s Property 7 27.0 73.0 N/A 86.7 Flowable 8 27.0 1.0 72.0 150 × 6 90.4Flowable 9 27.0 2.0 71.0 150 × 6 104.1 Flowable 10 27.0 3.0 70.0 150 × 6123.4 Flowable 11 27.0 4.0 69.0 150 × 6 127.5 Flowable 12 27.0 5.0 68.0150 × 6 158.4 Flowable 13 27.0 6.0 67.0 150 × 6 145.6 Flowable 14 27.01.0 72.0   150 × 5.5 99.7 Flowable 15 27.0 2.0 71.0   150 × 5.5 100.6Flowable 16 27.0 3.0 70.0   150 × 5.5 105.9 Flowable 17 27.0 4.0 69.0  150 × 5.5 114.7 Flowable 18 27.0 5.0 68.0   150 × 5.5 140.5 Flowable19 27.0 6.0 67.0   150 × 5.5 152.0 Flowable 20 27.0 0.6 72.4 3175 × 13210.6 Flowable 21 27.0 0.8 72.2 3175 × 13 232.8 Flowable 22 27.0 1.072.0 3175 × 13 272.4 Semi- flowable 23 27.0 1.5 71.5 3175 × 13 442.6Semi- flowable 24 27.0 2.0 71.0 3175 × 13 529.9 Semi- flowable 25 27.03.0 70.0 3175 × 13 634.0 Not flowable ¹Viscosity measured with ThermoElectron Corporation Haake Viscometer 7 Plus.Analysis of the Densities and Flexural Strengths of PolyurethaneComposites

Polyurethane composites were prepared, in duplicate, using fivedifferent mineral wool RF825 compositions (as described in Table 3). Thedensities and viscosities of the polyurethane composites are shown inTable 3.

The flexural strength of the composites was plotted as a function of thedensity (FIGS. 1 and 2). The mineral wool provided an increase of about20% in flexural strength to the polymeric composites.

TABLE 3 Effect of mineral wool fiber on the physical properties ofpolyurethane composites Content in Percent by Weight Average MineralAverage Flexural Stdev Wool Density Stdev Strength Flexural Fiber PURFly Ash pcf Density psi Strength 6.3 53.6 40.2 18.3 0.28 701 16.1 6.353.6 40.2 21.7 0.50 870 104.6 10.3 51.3 38.5 25.7 1.09 1189 122.3 6.353.6 40.2 25.6 0.20 1098 43.6 1.9 56.1 42.1 24.7 0.42 1000 27.8 1.9 56.142.1 18.4 0.46 666 95.6 10.3 51.3 38.5 17.7 0.32 641 74.5 0.0 57.1 42.922.0 0.78 628 52.8 4.1 54.8 41.1 22.7 0.49 904 37.3Analysis of the Densities and Flexural Strengths of PolyurethaneComposites

Six polyurethane composites were prepared, using varying compositions ofmineral wool RF825, sand, filler, and polyurethane (as described inTable 4). The densities and flexural strengths of the polyurethanecomposites are shown in Table 4.

The flexural strength of the composites was plotted as a function of thedensity (FIG. 3).

TABLE 4 Effect of mineral wool fiber on the physical properties ofpolyurethane composites Mineral Flexural Sample Wool, Sand,Polyurethane, Fly Strength, Density, Name % % % Ash, % psi pcf 1 7 053.5 39.5 1252 26.28 2 7 0 53.8 39.2 947 22.08 3 7 0 54.1 38.9 646 17.984 0 2 51.2 46.8 1028 26.51 5 0 2 51.3 46.7 762 22.24 6 0 2 51.7 46.3 56418.20

The compositions and methods of the appended claims are not limited inscope by the specific compositions and methods described herein, whichare intended as illustrations of a few aspects of the claims and anycompositions and methods that are functionally equivalent are intendedto fall within the scope of the claims. Various modifications of thecompositions and methods in addition to those shown and described hereinare intended to fall within the scope of the appended claims. Further,while only certain representative materials and method steps disclosedherein are specifically described, other combinations of the materialsand method steps also are intended to fall within the scope of theappended claims, even if not specifically recited. Thus, a combinationof steps, elements, components, or constituents may be explicitlymentioned herein; however, other combinations of steps, elements,components, and constituents are included, even though not explicitlystated. The term “comprising” and variations thereof as used herein isused synonymously with the term “including” and variations thereof andare open, non-limiting terms. Although the terms “comprising” and“including” have been used herein to describe various embodiments, theterms “consisting essentially of” and “consisting of” can be used inplace of “comprising” and “including” to provide for more specificembodiments and are also disclosed. As used in this disclosure and inthe appended claims, the singular forms “a”, “an”, “the”, include pluralreferents unless the context clearly dictates otherwise.

What is claimed is:
 1. A composite comprising: (a) a polymer; (b) from25% to 90% by weight of an inorganic filler comprising fly ash; and (c)a plurality of short length fibers having an average length of 650 μm orless.
 2. The composite of claim 1, wherein the short length fibers havean average aspect ratio of length to diameter of 5:1 to 250:1.
 3. Acomposite comprising: (a) a polymer; (b) from 25% to 90% by weight of aninorganic filler; and (c) a plurality of short length fibers having anaverage aspect ratio of length to diameter of 8:1 to 250:1, wherein theshort length fibers are selected from the group consisting of mineralwool, cellulose, wood fiber, saw dust, wood shavings, cotton, lint, andcombinations thereof.
 4. The composite of claim 1, wherein the shortlength fibers are selected from the group consisting of mineral wool,cellulose, wood fiber, saw dust, wood shavings, cotton, lint, andcombinations thereof.
 5. The composite of claim 3, wherein the shortlength fibers have an average length of from 50 μm to 650 μm.
 6. Thecomposite of claim 1, wherein the short length fibers have an averagelength of from 100 μm to 250 μm.
 7. The composite of claim 1, whereinthe short length fibers have an average diameter of from 1 to 20 μm. 8.The composite of claim 1, wherein the short length fibers are present inan amount from 0.5% to 15% by weight, based on the total weight of thecomposite.
 9. The composite of claim 1, wherein the inorganic filler ispresent in an amount from 50% to 80% by weight, based on the totalweight of the composite.
 10. The composite of claim 1, furthercomprising a plurality of glass fibers having a minimum length of 1 mm.11. The composite of claim 10, wherein the glass fiber is present in anamount from 0.5% to 10% by weight, based on the total weight of thecomposite.
 12. The composite of claim 1, wherein the polymer is selectedfrom the group consisting of polyolefins, ethylene copolymers,polystyrenes, polyvinyl chlorides, polyvinylidene chlorides, polyvinylacetates, polyacrylonitriles, polyamides, polyisobutylenes, polyacetals,chlorinated and fluorinated polymers, fluoroelastomers, fluorosilicones,polycarbonates, epoxies, phenolics, polyesters, acrylic polymers,acrylate polymers, polyurethanes, alkyds, silicones, styrene-butadienecopolymers, acrylonitrile-butadiene-styrene copolymers, nitrile rubbers,diallyl phthalates, melamines, polybutadienes, aramids, cellulosics,cellulose acetobutyrates, ionomers, parylenes, polyaryl ethers, polyarylsulfones, polyarylene sulfides, polyethersulfones, polyallomers,polyimides, polyamideimides, polymethylpentenes, polyphenylene oxides,polyphenylene sulfides, polysulfones, polyetherketones, polyetherimides,polyaryleneketones, polychloroprenes, and blends thereof.
 13. Thecomposite of claim 1, wherein the polymer is a polyurethane formed bythe reaction of at least one isocyanate selected from the groupconsisting of diisocyanates, polyisocyanates and mixtures thereof, andat least one polyol.
 14. The composite of claim 1, wherein the compositehas a density of 20 lb/ft³ to 60 lb/ft³.
 15. A building materialcomprising the composite of claim
 1. 16. A method of preparing apolyurethane composite, comprising: (a) mixing (1) 25% to 90% by weightof an inorganic filler based on the total weight of the composite; (2)at least one isocyanate selected from the group consisting ofdiisocyanates, polyisocyanates, and combinations thereof; (3) at leastone polyol; (4) a plurality of short length fibers having a length of650 μm or less; and (5) a catalyst; and (b) allowing the at least oneisocyanate and the at least one polyol to react in the presence of theinorganic filler, and the plurality of short length fibers to form thepolyurethane composite.
 17. The method of claim 16, wherein the shortlength fibers are selected from the group consisting of mineral wool,cellulose, wood fiber, saw dust, wood shavings, cotton, lint, andcombinations thereof.
 18. The composite of claim 3, wherein theinorganic filler comprises fly ash.
 19. A composite comprising: (a) apolymer; (b) from 25% to 90% by weight of an inorganic filler; (c) aplurality of short length fibers having an average length of 650 μm orless; and (d) a plurality of glass fibers having a minimum length of 1mm.
 20. The composite of claim 19, wherein the glass fibers are presentin an amount from 0.5% to 10% by weight, based on the total weight ofthe composite.
 21. A composite comprising: (a) a polymer; (b) from 25%to 90% by weight of an inorganic filler; (c) a plurality of short lengthfibers having an average length of 650 μm or less; and (d) a pluralityof glass fibers, wherein the glass fibers are present in an amount from0.5% to 10% by weight, based on the total weight of the composite.
 22. Acomposite comprising: (a) a polymer; (b) from 25% to 90% by weight of aninorganic filler; (c) a plurality of short length fibers having anaverage length of 650 μm or less; wherein the short length fibers areselected from the group consisting of mineral wool, cellulose, woodfiber, saw dust, wood shavings, cotton, lint, and combinations thereof.23. A method of preparing a polyurethane composite, comprising: (a)mixing (1) 25% to 90% by weight of an inorganic filler based on thetotal weight of the composite; (2) at least one isocyanate selected fromthe group consisting of diisocyanates, polyisocyanates, and combinationsthereof; (3) at least one polyol; and (4) a plurality of short lengthfibers having a length of 650 μm or less, wherein the short lengthfibers are selected from the group consisting of mineral wool,cellulose, wood fiber, saw dust, wood shavings, cotton, lint, andcombinations thereof; and (b) allowing the at least one isocyanate andthe at least one polyol to react in the presence of the inorganicfiller, and the plurality of short length fibers to form thepolyurethane composite.